1. Field of the Invention
The invention relates to a surgical stapling instrument, and more particularly to such an instrument for the joining together of tubular body organs.
2. Description of the Prior Art
The most common surgical method of joining two tubular body parts has involved the use of conventional thread sutures. This is, however, a difficult and time-consuming procedure. To avoid this, prior art workers have turned to other expedients such as clamping means of the type shown in U.S. Pat. No. 2,453,056. More recently, considerable interest has centered around the use of staples to join tubular body parts since this is an easier procedure and of even greater importance, is very much faster. It will be understood that the less time required for suturing, the shorter the length of time the patient must be maintained under anesthesia.
One approach has been to join the tubular body parts in end-to-end relationship by stapling means which engage the body parts externally. This is illustrated in U.S. Pat. Nos. 2,940,451 and 3,606,888. Another approach involved the joining of overlapped tubular body parts as taught in U.S. Pat. No. 3,638,652. Yet another approach again joined the tubular body parts substantially in end-to-end relationship, engaging the tubular parts internally and removing excess portions of the tubular parts adjacent the line or lines of staples through the use of a cylindrical scalpel or the like. Such stapling devices are taught and illustrated in U.S. Pat. Nos. 3,193,165; 3,388,847; 3,552,626 and 3,593,903. These last mentioned patents teach surgical instruments having a pistol grip and being actuated by trigger means.
The present invention is directed to an intralumenal anastomosis medical stapling device more nearly like those of the last mentioned patents, but free of laterally extending protrusions, grips or triggers. The surgical instrument of the present invention possesses a number of advantages not found in the prior art. For example, the staple suture line is placed by the instrument independently of the cutting action of the cylindrical scalpel. The unique driving mechanism of the instrument enables the instrument to be virtually symmetrical about its axis and makes it practical to provide two or more concentric staple suture lines. Means are provided to prevent over-forming or crushing of the staple sutures irrespective of the force used by the surgeon.
A first latch means is provided to assure that all of the parts are in their proper position during initial insertion and positioning of the instrument. A second latch means guarantees that the staple suture line cannot be implanted unless the gap between the staple carrier and the anvil plate is within the forming limits of the staples. Yet a third latch means assures that the circular scalpel cannot be actuated until the staple suture line is fully implanted and properly crimped. As a result of this, the instrument is sequentially controlled and can only be used correctly by the surgeon, eliminating chance of human error.
The construction of the instrument lends itself well to the use of low cost materials, such as plastic or the like, making it practical to construct the instrument as a single-use, disposable instrument. The construction of the instrument further lends itself to the employment of a single-use, disposable staple carrier and/or the use of a single-use, disposable anvil plate. When the balance of the instrument is intended to be reusable, it may be made of durable material appropriate for use in a surgical environment and capable of withstanding sterilization procedures, such as stainless steel or the like. Finally, the particular configuration of the staple driver actuator and the anvil shank will assure proper radial alignment of the anvil plate and the staple carrier, preventing irregular formation of the staple sutures.